jarsigner(1) JDK Commands jarsigner(1)
NAME
jarsigner - sign and verify Java Archive (JAR) files
SYNOPSIS
jarsigner [options] jar-file alias
jarsigner -verify [options] jar-file [alias ...]
jarsigner -version
options
The command-line options. See Options for jarsigner.
-verify
The -verify option can take zero or more keystore alias names
after the JAR file name. When the -verify option is specified,
the jarsigner command checks that the certificate used to verify
each signed entry in the JAR file matches one of the keystore
aliases. The aliases are defined in the keystore specified by
-keystore or the default keystore.
If you also specify the -strict option, and the jarsigner command
detects severe warnings, the message, "jar verified, with signer
errors" is displayed.
jar-file
The JAR file to be signed.
If you also specified the -strict option, and the jarsigner
command detected severe warnings, the message, "jar signed, with
signer errors" is displayed.
alias The aliases are defined in the keystore specified by -keystore or
the default keystore.
-version
The -version option prints the program version of jarsigner.
DESCRIPTION
The jarsigner tool has two purposes:
o To sign Java Archive (JAR) files.
o To verify the signatures and integrity of signed JAR files.
The JAR feature enables the packaging of class files, images, sounds, and
other digital data in a single file for faster and easier distribution.
A tool named jar enables developers to produce JAR files. (Technically,
any ZIP file can also be considered a JAR file, although when created by
the jar command or processed by the jarsigner command, JAR files also
contain a META-INF/MANIFEST.MF file.)
A digital signature is a string of bits that is computed from some data
(the data being signed) and the private key of an entity (a person,
company, and so on). Similar to a handwritten signature, a digital
signature has many useful characteristics:
o Its authenticity can be verified by a computation that uses the public
key corresponding to the private key used to generate the signature.
o It can't be forged, assuming the private key is kept secret.
o It is a function of the data signed and thus can't be claimed to be the
signature for other data as well.
o The signed data can't be changed. If the data is changed, then the
signature can't be verified as authentic.
To generate an entity's signature for a file, the entity must first have
a public/private key pair associated with it and one or more certificates
that authenticate its public key. A certificate is a digitally signed
statement from one entity that says that the public key of another entity
has a particular value.
The jarsigner command uses key and certificate information from a
keystore to generate digital signatures for JAR files. A keystore is a
database of private keys and their associated X.509 certificate chains
that authenticate the corresponding public keys. The keytool command is
used to create and administer keystores.
The jarsigner command uses an entity's private key to generate a
signature. The signed JAR file contains, among other things, a copy of
the certificate from the keystore for the public key corresponding to the
private key used to sign the file. The jarsigner command can verify the
digital signature of the signed JAR file using the certificate inside it
(in its signature block file).
The jarsigner command can generate signatures that include a time stamp
that enables a systems or deployer to check whether the JAR file was
signed while the signing certificate was still valid.
In addition, APIs allow applications to obtain the timestamp information.
At this time, the jarsigner command can only sign JAR files created by
the jar command or zip files. JAR files are the same as zip files,
except they also have a META-INF/MANIFEST.MF file. A
META-INF/MANIFEST.MF file is created when the jarsigner command signs a
zip file.
The default jarsigner command behavior is to sign a JAR or zip file. Use
the -verify option to verify a signed JAR file.
The jarsigner command also attempts to validate the signer's certificate
after signing or verifying. During validation, it checks the revocation
status of each certificate in the signer's certificate chain when the
-revCheck option is specified. If there is a validation error or any
other problem, the command generates warning messages. If you specify
the -strict option, then the command treats severe warnings as errors.
See Errors and Warnings.
KEYSTORE ALIASES
All keystore entities are accessed with unique aliases.
When you use the jarsigner command to sign a JAR file, you must specify
the alias for the keystore entry that contains the private key needed to
generate the signature. If no output file is specified, it overwrites
the original JAR file with the signed JAR file.
Keystores are protected with a password, so the store password must be
specified. You are prompted for it when you don't specify it on the
command line. Similarly, private keys are protected in a keystore with a
password, so the private key's password must be specified, and you are
prompted for the password when you don't specify it on the command line
and it isn't the same as the store password.
KEYSTORE LOCATION
The jarsigner command has a -keystore option for specifying the URL of
the keystore to be used. The keystore is by default stored in a file
named .keystore in the user's home directory, as determined by the
user.home system property.
Linux and macOS: user.home defaults to the user's home directory.
The input stream from the -keystore option is passed to the KeyStore.load
method. If NONE is specified as the URL, then a null stream is passed to
the KeyStore.load method. NONE should be specified when the KeyStore
class isn't file based, for example, when it resides on a hardware token
device.
KEYSTORE IMPLEMENTATION
The KeyStore class provided in the java.security package supplies a
number of well-defined interfaces to access and modify the information in
a keystore. You can have multiple different concrete implementations,
where each implementation is for a particular type of keystore.
Currently, there are two command-line tools that use keystore
implementations (keytool and jarsigner).
The default keystore implementation is PKCS12. This is a cross platform
keystore based on the RSA PKCS12 Personal Information Exchange Syntax
Standard. This standard is primarily meant for storing or transporting a
user's private keys, certificates, and miscellaneous secrets. There is
another built-in implementation, provided by Oracle. It implements the
keystore as a file with a proprietary keystore type (format) named JKS.
It protects each private key with its individual password, and also
protects the integrity of the entire keystore with a (possibly different)
password.
Keystore implementations are provider-based, which means the application
interfaces supplied by the KeyStore class are implemented in terms of a
Service Provider Interface (SPI). There is a corresponding abstract
KeystoreSpi class, also in the java.security package, that defines the
Service Provider Interface methods that providers must implement. The
term provider refers to a package or a set of packages that supply a
concrete implementation of a subset of services that can be accessed by
the Java Security API. To provide a keystore implementation, clients
must implement a provider and supply a KeystoreSpi subclass
implementation, as described in How to Implement a Provider in the Java
Cryptography Architecture
[https://www.oracle.com/pls/topic/lookup?ctx=en/java/javase&id=security_guide_implement_provider_jca].
Applications can choose different types of keystore implementations from
different providers, with the getInstance factory method in the KeyStore
class. A keystore type defines the storage and data format of the
keystore information and the algorithms used to protect private keys in
the keystore and the integrity of the keystore itself. Keystore
implementations of different types aren't compatible.
The jarsigner commands can read file-based keystores from any location
that can be specified using a URL. In addition, these commands can read
non-file-based keystores such as those provided by MSCAPI on Windows and
PKCS11 on all platforms.
For the jarsigner and keytool commands, you can specify a keystore type
at the command line with the -storetype option.
If you don't explicitly specify a keystore type, then the tools choose a
keystore implementation based on the value of the keystore.type property
specified in the security properties file. The security properties file
is called java.security, and it resides in the JDK security properties
directory, java.home/conf/security.
Each tool gets the keystore.type value and then examines all the
installed providers until it finds one that implements keystores of that
type. It then uses the keystore implementation from that provider.
The KeyStore class defines a static method named getDefaultType that lets
applications retrieve the value of the keystore.type property. The
following line of code creates an instance of the default keystore type
as specified in the keystore.type property:
KeyStore keyStore =
KeyStore.getInstance(KeyStore.getDefaultType());
The default keystore type is pkcs12, which is a cross platform keystore
based on the RSA PKCS12 Personal Information Exchange Syntax Standard.
This is specified by the following line in the security properties file:
keystore.type=pkcs12
Case doesn't matter in keystore type designations. For example, JKS is
the same as jks.
To have the tools utilize a keystore implementation other than the
default, you can change that line to specify a different keystore type.
For example, if you want to use the Oracle's jks keystore implementation,
then change the line to the following:
keystore.type=jks
SUPPORTED ALGORITHMS
By default, the jarsigner command signs a JAR file using one of the
following algorithms and block file extensions depending on the type and
size of the private key:
Default Signature Algorithms and Block File Extensions
keyalg key size default sigalg block file
extension
---------------------------------------------------------
DSA any size SHA256withDSA .DSA
RSA < 624 SHA256withRSA .RSA
<= 7680 SHA384withRSA
> 7680 SHA512withRSA
EC < 512 SHA384withECDSA .EC
>= 512 SHA512withECDSA
RSASSA-PSS[1] < 624 RSASSA-PSS (with .RSA
SHA-256)
<= 7680 RSASSA-PSS (with
SHA-384)
> 7680 RSASSA-PSS (with
SHA-512)
EdDSA[2] EdDSA .EC
ML-DSA[2] ML-DSA .DSA
1. If an RSASSA-PSS key is encoded with parameters, then jarsigner will
use the same parameters in the signature. Otherwise, jarsigner will
use parameters that are determined by the size of the key as specified
in the table above. For example, an 3072-bit RSASSA-PSS key will use
RSASSA-PSS as the signature algorithm and SHA-384 as the hash and MGF1
algorithms.
2. Modern digital signature algorithms such as EdDSA and ML-DSA use the
same name for both the key and signature algorithms. Only the
signature algorithm with the same name can be used with a given key
algorithm. The specific signature parameter set (for example, Ed25519
or Ed448 for EdDSA) is the same as that of the key.
If a key algorithm is not listed in this table, the .DSA block file
extension is always used.
These default signature algorithms can be overridden by using the -sigalg
option.
The jarsigner command uses the jdk.jar.disabledAlgorithms and
jdk.security.legacyAlgorithms security properties to determine which
algorithms are considered a security risk. If the JAR file was signed
with any algorithms that are disabled, it will be treated as an unsigned
JAR file. If the JAR file was signed with any legacy algorithms, it will
be treated as signed with an informational warning to inform users that
the legacy algorithm will be disabled in a future update. For detailed
verification output, include -J-Djava.security.debug=jar. The
jdk.jar.disabledAlgorithms and jdk.security.legacyAlgorithms security
properties are defined in the java.security file (located in the JDK's
$JAVA_HOME/conf/security directory).
Note:
In order to improve out of the box security, default key size and
signature algorithm names are periodically updated to stronger values
with each release of the JDK. If interoperability with older releases of
the JDK is important, please make sure the defaults are supported by
those releases, or alternatively use the -sigalg option to override the
default values at your own risk.
THE SIGNED JAR FILE
When the jarsigner command is used to sign a JAR file, the output signed
JAR file is exactly the same as the input JAR file, except that it has
two additional files placed in the META-INF directory:
o A signature file with an .SF extension
o A signature block file with a .DSA, .RSA, or .EC extension
The base file names for these two files come from the value of the
-sigfile option. For example, when the option is -sigfile MKSIGN, the
files are named MKSIGN.SF and MKSIGN.RSA. In this document, we assume
the signer always uses an RSA key.
If no -sigfile option appears on the command line, then the base file
name for the .SF and the signature block files is the first 8 characters
of the alias name specified on the command line, all converted to
uppercase. If the alias name has fewer than 8 characters, then the full
alias name is used. If the alias name contains any characters that
aren't allowed in a signature file name, then each such character is
converted to an underscore (_) character in forming the file name. Valid
characters include letters, digits, underscores, and hyphens.
SIGNATURE FILE
A signature file (.SF file) looks similar to the manifest file that is
always included in a JAR file when the jarsigner command is used to sign
the file. For each source file included in the JAR file, the .SF file
has two lines, such as in the manifest file, that list the following:
o File name
o Name of the digest algorithm (SHA)
o SHA digest value
Note:
The name of the digest algorithm (SHA) and the SHA digest value are on
the same line.
In the manifest file, the SHA digest value for each source file is the
digest (hash) of the binary data in the source file. In the .SF file,
the digest value for a specified source file is the hash of the two lines
in the manifest file for the source file.
The signature file, by default, includes a header with a hash of the
whole manifest file. The header also contains a hash of the manifest
header. The presence of the header enables verification optimization.
See JAR File Verification.
SIGNATURE BLOCK FILE
The .SF file is signed and the signature is placed in the signature block
file. This file also contains, encoded inside it, the certificate or
certificate chain from the keystore that authenticates the public key
corresponding to the private key used for signing. The file has the
extension .DSA, .RSA, or .EC, depending on the key algorithm used. See
the table in Supported Algorithms.
SIGNATURE TIME STAMP
The jarsigner command used with the following options generates and
stores a signature time stamp when signing a JAR file:
o -tsa url
o -tsacert alias
o -tsapolicyid policyid
o -tsadigestalg algorithm
See Options for jarsigner.
JAR FILE VERIFICATION
A successful JAR file verification occurs when the signatures are valid,
and none of the files that were in the JAR file when the signatures were
generated have changed since then. JAR file verification involves the
following steps:
1. Verify the signature of the .SF file.
The verification ensures that the signature stored in each signature
block file was generated using the private key corresponding to the
public key whose certificate (or certificate chain) also appears in
the signature block file. It also ensures that the signature is a
valid signature of the corresponding signature (.SF) file, and thus
the .SF file wasn't tampered with.
2. Verify the digest listed in each entry in the .SF file with each
corresponding section in the manifest.
The .SF file by default includes a header that contains a hash of the
entire manifest file. When the header is present, the verification
can check to see whether or not the hash in the header matches the
hash of the manifest file. If there is a match, then verification
proceeds to the next step.
If there is no match, then a less optimized verification is required
to ensure that the hash in each source file information section in
the .SF file equals the hash of its corresponding section in the
manifest file. See Signature File.
One reason the hash of the manifest file that is stored in the .SF
file header might not equal the hash of the current manifest file is
that it might contain sections for newly added files after the file
was signed. For example, suppose one or more files were added to the
signed JAR file (using the jar tool) that already contains a
signature and a .SF file. If the JAR file is signed again by a
different signer, then the manifest file is changed (sections are
added to it for the new files by the jarsigner tool) and a new .SF
file is created, but the original .SF file is unchanged. A
verification is still considered successful if none of the files that
were in the JAR file when the original signature was generated have
been changed since then. This is because the hashes in the
non-header sections of the .SF file equal the hashes of the
corresponding sections in the manifest file.
3. Read each file in the JAR file that has an entry in the .SF file.
While reading, compute the file's digest and compare the result with
the digest for this file in the manifest section. The digests should
be the same or verification fails.
If any serious verification failures occur during the verification
process, then the process is stopped and a security exception is
thrown. The jarsigner command catches and displays the exception.
4. Check for disabled algorithm usage. See Supported Algorithms.
Note:
You should read any addition warnings (or errors if you specified the
-strict option), as well as the content of the certificate (by specifying
the -verbose and -certs options) to determine if the signature can be
trusted.
MULTIPLE SIGNATURES FOR A JAR FILE
A JAR file can be signed by multiple people by running the jarsigner
command on the file multiple times and specifying the alias for a
different person each time, as follows:
jarsigner myBundle.jar susan
jarsigner myBundle.jar kevin
When a JAR file is signed multiple times, there are multiple .SF and
signature block files in the resulting JAR file, one pair for each
signature. In the previous example, the output JAR file includes files
with the following names:
SUSAN.SF
SUSAN.RSA
KEVIN.SF
KEVIN.RSA
OPTIONS FOR JARSIGNER
The following sections describe the options for the jarsigner. Be aware
of the following standards:
o All option names are preceded by a hyphen sign (-).
o The options can be provided in any order.
o Items that are in italics or underlined (option values) represent the
actual values that must be supplied.
o The -storepass, -keypass, -sigfile, -sigalg, -digestalg, -signedjar,
and TSA-related options are only relevant when signing a JAR file; they
aren't relevant when verifying a signed JAR file. The -keystore option
is relevant for signing and verifying a JAR file. In addition, aliases
are specified when signing and verifying a JAR file.
-keystore url
Specifies the URL that tells the keystore location. This defaults to
the file .keystore in the user's home directory, as determined by the
user.home system property.
A keystore is required when signing. You must explicitly specify a
keystore when the default keystore doesn't exist or if you want to use
one other than the default.
A keystore isn't required when verifying, but if one is specified or
the default exists and the -verbose option was also specified, then
additional information is output regarding whether or not any of the
certificates used to verify the JAR file are contained in that
keystore.
The -keystore argument can be a file name and path specification rather
than a URL, in which case it is treated the same as a file: URL, for
example, the following are equivalent:
o -keystore filePathAndName
o -keystore file:filePathAndName
If the Sun PKCS #11 provider was configured in the java.security
security properties file (located in the JDK's $JAVA_HOME/conf/security
directory), then the keytool and jarsigner tools can operate on the
PKCS #11 token by specifying these options:
-keystore NONE -storetype PKCS11
For example, the following command lists the contents of the configured
PKCS#11 token:
keytool -keystore NONE -storetype PKCS11 -list
-storepass [:env | :file] argument
Specifies the password that is required to access the keystore. This
is only needed when signing (not verifying) a JAR file. In that case,
if a -storepass option isn't provided at the command line, then the
user is prompted for the password.
If the modifier env or file isn't specified, then the password has the
value argument. Otherwise, the password is retrieved as follows:
o env: Retrieve the password from the environment variable named
argument.
o file: Retrieve the password from the file named argument.
Note:
The password shouldn't be specified on the command line or in a script
unless it is for testing purposes, or you are on a secure system.
-storetype storetype
Specifies the type of keystore to be instantiated. The default
keystore type is the one that is specified as the value of the
keystore.type property in the security properties file, which is
returned by the static getDefaultType method in java.security.KeyStore.
The PIN for a PKCS #11 token can also be specified with the -storepass
option. If none is specified, then the keytool and jarsigner commands
prompt for the token PIN. If the token has a protected authentication
path (such as a dedicated PIN-pad or a biometric reader), then the
-protected option must be specified and no password options can be
specified.
-keypass [:env | :file] argument -certchain file
Specifies the password used to protect the private key of the keystore
entry addressed by the alias specified on the command line. The
password is required when using jarsigner to sign a JAR file. If no
password is provided on the command line, and the required password is
different from the store password, then the user is prompted for it.
If the modifier env or file isn't specified, then the password has the
value argument. Otherwise, the password is retrieved as follows:
o env: Retrieve the password from the environment variable named
argument.
o file: Retrieve the password from the file named argument.
Note:
The password shouldn't be specified on the command line or in a script
unless it is for testing purposes, or you are on a secure system.
-certchain file
Specifies the certificate chain to be used when the certificate chain
associated with the private key of the keystore entry that is addressed
by the alias specified on the command line isn't complete. This can
happen when the keystore is located on a hardware token where there
isn't enough capacity to hold a complete certificate chain. The file
can be a sequence of concatenated X.509 certificates, or a single
PKCS#7 formatted data block, either in binary encoding format or in
printable encoding format (also known as Base64 encoding) as defined by
Internet RFC 1421 Certificate Encoding Standard
[http://tools.ietf.org/html/rfc1421].
-sigfile file
Specifies the base file name to be used for the generated .SF and
signature block files. For example, if file is DUKESIGN, then the
generated .SF and signature block files are named DUKESIGN.SF and
DUKESIGN.RSA, and placed in the META-INF directory of the signed JAR
file.
The characters in the file must come from the set a-zA-Z0-9_-. Only
letters, numbers, underscore, and hyphen characters are allowed. All
lowercase characters are converted to uppercase for the .SF and
signature block file names.
If no -sigfile option appears on the command line, then the base file
name for the .SF and signature block files is the first 8 characters of
the alias name specified on the command line, all converted to upper
case. If the alias name has fewer than 8 characters, then the full
alias name is used. If the alias name contains any characters that
aren't valid in a signature file name, then each such character is
converted to an underscore (_) character to form the file name.
-signedjar file
Specifies the name of signed JAR file.
-digestalg algorithm
Specifies the name of the message digest algorithm to use when
digesting the entries of a JAR file.
For a list of standard message digest algorithm names, see the Java
Security Standard Algorithm Names Specification.
If this option isn't specified, then SHA-384 is used. There must
either be a statically installed provider supplying an implementation
of the specified algorithm or the user must specify one with the
-addprovider or -providerClass options; otherwise, the command will not
succeed.
-sigalg algorithm
Specifies the name of the signature algorithm to use to sign the JAR
file.
This algorithm must be compatible with the private key used to sign the
JAR file. If this option isn't specified, then use a default algorithm
matching the private key as described in the Supported Algorithms
section. There must either be a statically installed provider
supplying an implementation of the specified algorithm or you must
specify one with the -addprovider or -providerClass option; otherwise,
the command doesn't succeed.
For a list of standard signature algorithm names, see the Java Security
Standard Algorithm Names Specification.
-verify
Verifies a signed JAR file.
-verbose[:suboptions]
When the -verbose option appears on the command line, it indicates that
the jarsigner use the verbose mode when signing or verifying with the
suboptions determining how much information is shown. This causes the
, which causes jarsigner to output extra information about the progress
of the JAR signing or verification. The suboptions can be all,
grouped, or summary.
If the -certs option is also specified, then the default mode (or
suboption all) displays each entry as it is being processed, and after
that, the certificate information for each signer of the JAR file.
If the -certs and the -verbose:grouped suboptions are specified, then
entries with the same signer info are grouped and displayed together
with their certificate information.
If -certs and the -verbose:summary suboptions are specified, then
entries with the same signer information are grouped and displayed
together with their certificate information.
Details about each entry are summarized and displayed as one entry (and
more). See Example of Verifying a Signed JAR File and Example of
Verification with Certificate Information.
-certs
If the -certs option appears on the command line with the -verify and
-verbose options, then the output includes certificate information for
each signer of the JAR file. This information includes the name of the
type of certificate (stored in the signature block file) that certifies
the signer's public key, and if the certificate is an X.509 certificate
(an instance of the java.security.cert.X509Certificate), then the
distinguished name of the signer.
The keystore is also examined. If no keystore value is specified on
the command line, then the default keystore file (if any) is checked.
If the public key certificate for a signer matches an entry in the
keystore, then the alias name for the keystore entry for that signer is
displayed in parentheses.
-revCheck
This option enables revocation checking of certificates when signing or
verifying a JAR file. The jarsigner command attempts to make network
connections to fetch OCSP responses and CRLs if the -revCheck option is
specified on the command line. Note that revocation checks are not
enabled unless this option is specified.
-tsa url
If -tsa http://example.tsa.url appears on the command line when signing
a JAR file then a time stamp is generated for the signature. The URL,
http://example.tsa.url, identifies the location of the Time Stamping
Authority (TSA) and overrides any URL found with the -tsacert option.
The -tsa option doesn't require the TSA public key certificate to be
present in the keystore.
To generate the time stamp, jarsigner communicates with the TSA with
the Time-Stamp Protocol (TSP) defined in RFC 3161. When successful,
the time stamp token returned by the TSA is stored with the signature
in the signature block file.
-tsacert alias
When -tsacert alias appears on the command line when signing a JAR
file, a time stamp is generated for the signature. The alias
identifies the TSA public key certificate in the keystore that is in
effect. The entry's certificate is examined for a Subject Information
Access extension that contains a URL identifying the location of the
TSA.
The TSA public key certificate must be present in the keystore when
using the -tsacert option.
-tsapolicyid policyid
Specifies the object identifier (OID) that identifies the policy ID to
be sent to the TSA server. If this option isn't specified, no policy
ID is sent and the TSA server will choose a default policy ID.
Object identifiers are defined by X.696, which is an ITU
Telecommunication Standardization Sector (ITU-T) standard. These
identifiers are typically period-separated sets of non-negative digits
like 1.2.3.4, for example.
-tsadigestalg algorithm
Specifies the message digest algorithm that is used to generate the
message imprint to be sent to the TSA server. If this option isn't
specified, SHA-384 will be used.
See Supported Algorithms.
For a list of standard message digest algorithm names, see the Java
Security Standard Algorithm Names Specification.
-internalsf
In the past, the signature block file generated when a JAR file was
signed included a complete encoded copy of the .SF file (signature
file) also generated. This behavior has been changed. To reduce the
overall size of the output JAR file, the signature block file by
default doesn't contain a copy of the .SF file anymore. If -internalsf
appears on the command line, then the old behavior is utilized. This
option is useful for testing. In practice, don't use the -internalsf
option because it incurs higher overhead.
-sectionsonly
If the -sectionsonly option appears on the command line, then the .SF
file (signature file) generated when a JAR file is signed doesn't
include a header that contains a hash of the whole manifest file. It
contains only the information and hashes related to each individual
source file included in the JAR file. See Signature File.
By default, this header is added, as an optimization. When the header
is present, whenever the JAR file is verified, the verification can
first check to see whether the hash in the header matches the hash of
the whole manifest file. When there is a match, verification proceeds
to the next step. When there is no match, it is necessary to do a less
optimized verification that the hash in each source file information
section in the .SF file equals the hash of its corresponding section in
the manifest file. See JAR File Verification.
The -sectionsonly option is primarily used for testing. It shouldn't
be used other than for testing because using it incurs higher overhead.
-protected
Values can be either true or false. Specify true when a password must
be specified through a protected authentication path such as a
dedicated PIN reader.
-providerName providerName
If more than one provider was configured in the java.security security
properties file, then you can use the -providerName option to target a
specific provider instance. The argument to this option is the name of
the provider.
For the Oracle PKCS #11 provider, providerName is of the form
SunPKCS11-TokenName, where TokenName is the name suffix that the
provider instance has been configured with, as detailed in the
configuration attributes table. For example, the following command
lists the contents of the PKCS #11 keystore provider instance with name
suffix SmartCard:
jarsigner -keystore NONE -storetype PKCS11 -providerName
SunPKCS11-SmartCard -list
-addprovider name [-providerArg arg]
Adds a security provider by name (such as SunPKCS11) and an optional
configure argument. The value of the security provider is the name of
a security provider that is defined in a module.
Used with the -providerArg ConfigFilePath option, the keytool and
jarsigner tools install the provider dynamically and use ConfigFilePath
for the path to the token configuration file. The following example
shows a command to list a PKCS #11 keystore when the Oracle PKCS #11
provider wasn't configured in the security properties file.
jarsigner -keystore NONE -storetype PKCS11 -addprovider
SunPKCS11 -providerArg /mydir1/mydir2/token.config
-providerClass provider-class-name [-providerArg arg]
Used to specify the name of cryptographic service provider's master
class file when the service provider isn't listed in the java.security
security properties file. Adds a security provider by fully-qualified
class name and an optional configure argument.
Note:
The preferred way to load PKCS11 is by using modules. See
-addprovider.
-providerPath classpath
Used to specify the classpath for providers specified by the
-providerClass option. Multiple paths should be separated by the
system-dependent path-separator character.
-Jjavaoption
Passes through the specified javaoption string directly to the Java
interpreter. The jarsigner command is a wrapper around the
interpreter. This option shouldn't contain any spaces. It is useful
for adjusting the execution environment or memory usage. For a list of
possible interpreter options, type java -h or java -X at the command
line.
-strict
During the signing or verifying process, the command may issue warning
messages. If you specify this option, the exit code of the tool
reflects the severe warning messages that this command found. See
Errors and Warnings.
-conf url
Specifies a pre-configured options file. Read the keytool
documentation for details. The property keys supported are
"jarsigner.all" for all actions, "jarsigner.sign" for signing, and
"jarsigner.verify" for verification. jarsigner arguments including the
JAR file name and alias name(s) cannot be set in this file.
-version
Prints the program version.
ERRORS AND WARNINGS
During the signing or verifying process, the jarsigner command may issue
various errors or warnings.
If there is a failure, the jarsigner command exits with code 1. If there
is no failure, but there are one or more severe warnings, the jarsigner
command exits with code 0 when the -strict option is not specified, or
exits with the OR-value of the warning codes when the -strict is
specified. If there is only informational warnings or no warning at all,
the command always exits with code 0.
For example, if a certificate used to sign an entry is expired and has a
KeyUsage extension that doesn't allow it to sign a file, the jarsigner
command exits with code 12 (=4+8) when the -strict option is specified.
Note: Exit codes are reused because only the values from 0 to 255 are
legal on Linux and macOS.
The following sections describes the names, codes, and descriptions of
the errors and warnings that the jarsigner command can issue.
FAILURE
Reasons why the jarsigner command fails include (but aren't limited to) a
command line parsing error, the inability to find a keypair to sign the
JAR file, or the verification of a signed JAR fails.
failure
Code 1. The signing or verifying fails.
SEVERE WARNINGS
Note:
Severe warnings are reported as errors if you specify the -strict option.
Reasons why the jarsigner command issues a severe warning include the
certificate used to sign the JAR file has an error or the signed JAR file
has other problems.
hasExpiredCert
Code 4. This JAR contains entries whose signer certificate has
expired.
hasExpiredTsaCert
Code 4. The timestamp has expired.
notYetValidCert
Code 4. This JAR contains entries whose signer certificate isn't
yet valid.
chainNotValidated
Code 4. This JAR contains entries whose certificate chain isn't
validated.
tsaChainNotValidated
Code 64. The timestamp is invalid.
signerSelfSigned
Code 4. This JAR contains entries whose signer certificate is
self signed.
disabledAlg
Code 4. An algorithm used is considered a security risk and is
disabled.
badKeyUsage
Code 8. This JAR contains entries whose signer certificate's
KeyUsage extension doesn't allow code signing.
badExtendedKeyUsage
Code 8. This JAR contains entries whose signer certificate's
ExtendedKeyUsage extension doesn't allow code signing.
badNetscapeCertType
Code 8. This JAR contains entries whose signer certificate's
NetscapeCertType extension doesn't allow code signing.
hasUnsignedEntry
Code 16. This JAR contains unsigned entries which haven't been
integrity-checked.
notSignedByAlias
Code 32. This JAR contains signed entries which aren't signed by
the specified alias(es).
aliasNotInStore
Code 32. This JAR contains signed entries that aren't signed by
alias in this keystore.
tsaChainNotValidated
Code 64. This JAR contains entries whose TSA certificate chain is
invalid.
INFORMATIONAL WARNINGS
Informational warnings include those that aren't errors but regarded as
bad practice. They don't have a code.
extraAttributesDetected
The POSIX file permissions and/or symlink attributes are detected
during signing or verifying a JAR file. The jarsigner tool
preserves these attributes in the newly signed file but warns that
these attributes are unsigned and not protected by the signature.
hasExpiringCert
This JAR contains entries whose signer certificate expires within
six months.
hasExpiringTsaCert
The timestamp will expire within one year on YYYY-MM-DD.
hasMultipleManifests
This JAR contained multiple manifest files. During signing, one
of the files was selected, and the others were discarded.
hasNonexistentEntries
This JAR contains signed entries for files that do not exist.
internalInconsistenciesDetected
This JAR contains internal inconsistencies detected during
verification that may result in different contents when reading
via JarFile and JarInputStream.
legacyAlg
An algorithm used is considered a security risk but not disabled.
noTimestamp
This JAR contains signatures that doesn't include a timestamp.
Without a timestamp, users may not be able to validate this JAR
file after the signer certificate's expiration date (YYYY-MM-DD)
or after any future revocation date.
EXAMPLE OF SIGNING A JAR FILE
Use the following command to sign bundle.jar with the private key of a
user whose keystore alias is jane in a keystore named mystore in the
working directory and name the signed JAR file sbundle.jar:
jarsigner -keystore /working/mystore -storepass keystore_password
-keypass private_key_password -signedjar sbundle.jar bundle.jar
jane
There is no -sigfile specified in the previous command so the generated
.SF and signature block files to be placed in the signed JAR file have
default names based on the alias name. They are named JANE.SF and
JANE.RSA.
If you want to be prompted for the store password and the private key
password, then you could shorten the previous command to the following:
jarsigner -keystore /working/mystore -signedjar sbundle.jar
bundle.jar jane
If the keystore is the default keystore (.keystore in your home
directory), then you don't need to specify a keystore, as follows:
jarsigner -signedjar sbundle.jar bundle.jar jane
If you want the signed JAR file to overwrite the input JAR file
(bundle.jar), then you don't need to specify a -signedjar option, as
follows:
jarsigner bundle.jar jane
EXAMPLE OF VERIFYING A SIGNED JAR FILE
To verify a signed JAR file to ensure that the signature is valid and the
JAR file wasn't been tampered with, use a command such as the following:
jarsigner -verify ButtonDemo.jar
When the verification is successful, jar verified is displayed.
Otherwise, an error message is displayed. You can get more information
when you use the -verbose option. A sample use of jarsigner with the
-verbose option follows:
jarsigner -verify -verbose ButtonDemo.jar
s 866 Tue Sep 12 20:08:48 EDT 2017 META-INF/MANIFEST.MF
825 Tue Sep 12 20:08:48 EDT 2017 META-INF/ORACLE_C.SF
7475 Tue Sep 12 20:08:48 EDT 2017 META-INF/ORACLE_C.RSA
0 Tue Sep 12 20:07:54 EDT 2017 META-INF/
0 Tue Sep 12 20:07:16 EDT 2017 components/
0 Tue Sep 12 20:07:16 EDT 2017 components/images/
sm 523 Tue Sep 12 20:07:16 EDT 2017 components/ButtonDemo$1.class
sm 3440 Tue Sep 12 20:07:16 EDT 2017 components/ButtonDemo.class
sm 2346 Tue Sep 12 20:07:16 EDT 2017 components/ButtonDemo.jnlp
sm 172 Tue Sep 12 20:07:16 EDT 2017 components/images/left.gif
sm 235 Tue Sep 12 20:07:16 EDT 2017 components/images/middle.gif
sm 172 Tue Sep 12 20:07:16 EDT 2017 components/images/right.gif
s = signature was verified
m = entry is listed in manifest
k = at least one certificate was found in keystore
- Signed by "CN="Oracle America, Inc.", OU=Software Engineering, O="Oracle America, Inc.", L=Redwood City, ST=California, C=US"
Digest algorithm: SHA-256
Signature algorithm: SHA256withRSA, 2048-bit key
Timestamped by "CN=Symantec Time Stamping Services Signer - G4, O=Symantec Corporation, C=US" on Tue Sep 12 20:08:49 UTC 2017
Timestamp digest algorithm: SHA-1
Timestamp signature algorithm: SHA1withRSA, 2048-bit key
jar verified.
The signer certificate expired on 2018-02-01. However, the JAR will be valid until the timestamp expires on 2020-12-29.
EXAMPLE OF VERIFICATION WITH CERTIFICATE INFORMATION
If you specify the -certs option with the -verify and -verbose options,
then the output includes certificate information for each signer of the
JAR file. The information includes the certificate type, the signer
distinguished name information (when it is an X.509 certificate), and in
parentheses, the keystore alias for the signer when the public key
certificate in the JAR file matches the one in a keystore entry, for
example:
jarsigner -keystore $JAVA_HOME/lib/security/cacerts -verify -verbose -certs ButtonDemo.jar
s k 866 Tue Sep 12 20:08:48 EDT 2017 META-INF/MANIFEST.MF
>>> Signer
X.509, CN="Oracle America, Inc.", OU=Software Engineering, O="Oracle America, Inc.", L=Redwood City, ST=California, C=US
[certificate is valid from 2017-01-30, 7:00 PM to 2018-02-01, 6:59 PM]
X.509, CN=Symantec Class 3 SHA256 Code Signing CA, OU=Symantec Trust Network, O=Symantec Corporation, C=US
[certificate is valid from 2013-12-09, 7:00 PM to 2023-12-09, 6:59 PM]
X.509, CN=VeriSign Class 3 Public Primary Certification Authority - G5, OU="(c) 2006 VeriSign, Inc. - For authorized use only", OU=VeriSign Trust Network, O="VeriSign, Inc.", C=US (verisignclass3g5ca [jdk])
[trusted certificate]
>>> TSA
X.509, CN=Symantec Time Stamping Services Signer - G4, O=Symantec Corporation, C=US
[certificate is valid from 2012-10-17, 8:00 PM to 2020-12-29, 6:59 PM]
X.509, CN=Symantec Time Stamping Services CA - G2, O=Symantec Corporation, C=US
[certificate is valid from 2012-12-20, 7:00 PM to 2020-12-30, 6:59 PM]
825 Tue Sep 12 20:08:48 EDT 2017 META-INF/ORACLE_C.SF
7475 Tue Sep 12 20:08:48 EDT 2017 META-INF/ORACLE_C.RSA
0 Tue Sep 12 20:07:54 EDT 2017 META-INF/
0 Tue Sep 12 20:07:16 EDT 2017 components/
0 Tue Sep 12 20:07:16 EDT 2017 components/images/
smk 523 Tue Sep 12 20:07:16 EDT 2017 components/ButtonDemo$1.class
[entry was signed on 2017-09-12, 4:08 PM]
>>> Signer
X.509, CN="Oracle America, Inc.", OU=Software Engineering, O="Oracle America, Inc.", L=Redwood City, ST=California, C=US
[certificate is valid from 2017-01-30, 7:00 PM to 2018-02-01, 6:59 PM]
X.509, CN=Symantec Class 3 SHA256 Code Signing CA, OU=Symantec Trust Network, O=Symantec Corporation, C=US
[certificate is valid from 2013-12-09, 7:00 PM to 2023-12-09, 6:59 PM]
X.509, CN=VeriSign Class 3 Public Primary Certification Authority - G5, OU="(c) 2006 VeriSign, Inc. - For authorized use only", OU=VeriSign Trust Network, O="VeriSign, Inc.", C=US (verisignclass3g5ca [jdk])
[trusted certificate]
>>> TSA
X.509, CN=Symantec Time Stamping Services Signer - G4, O=Symantec Corporation, C=US
[certificate is valid from 2012-10-17, 8:00 PM to 2020-12-29, 6:59 PM]
X.509, CN=Symantec Time Stamping Services CA - G2, O=Symantec Corporation, C=US
[certificate is valid from 2012-12-20, 7:00 PM to 2020-12-30, 6:59 PM]
smk 3440 Tue Sep 12 20:07:16 EDT 2017 components/ButtonDemo.class
...
smk 2346 Tue Sep 12 20:07:16 EDT 2017 components/ButtonDemo.jnlp
...
smk 172 Tue Sep 12 20:07:16 EDT 2017 components/images/left.gif
...
smk 235 Tue Sep 12 20:07:16 EDT 2017 components/images/middle.gif
...
smk 172 Tue Sep 12 20:07:16 EDT 2017 components/images/right.gif
...
s = signature was verified
m = entry is listed in manifest
k = at least one certificate was found in keystore
- Signed by "CN="Oracle America, Inc.", OU=Software Engineering, O="Oracle America, Inc.", L=Redwood City, ST=California, C=US"
Digest algorithm: SHA-256
Signature algorithm: SHA256withRSA, 2048-bit key
Timestamped by "CN=Symantec Time Stamping Services Signer - G4, O=Symantec Corporation, C=US" on Tue Sep 12 20:08:49 UTC 2017
Timestamp digest algorithm: SHA-1
Timestamp signature algorithm: SHA1withRSA, 2048-bit key
jar verified.
The signer certificate expired on 2018-02-01. However, the JAR will be valid until the timestamp expires on 2020-12-29.
If the certificate for a signer isn't an X.509 certificate, then there is
no distinguished name information. In that case, just the certificate
type and the alias are shown. For example, if the certificate is a PGP
certificate, and the alias is bob, then you would get: PGP, (bob).
JDK 27.0.1 2026 jarsigner(1)
openjdk27-zulu 27.30.107 - Generated Tue Oct 27 07:41:28 CDT 2026